Acoustic tile with sound-reflective polymeric layer bonded to fibrous layer



Jan. 18, 1966 R R POTTASH 3,229,785

ACOUSTIC TILE WITH soUND-REFLEGTIVE PoLYMERIc LAYER BoNDED To FIBRoUs LAYER Filed Jan. 25, 1964 RUBEN R. POTTASH www ATTORNEY United States Patent O 3,229,785 ACOUSTIC TILE WITH SOUND-REFLECTIVE POLYMERIC LAYER BONDED TO FIBROUS LAYER Ruben R. Pottash, 1205 Wyngate Road, Wynnewood, Pa. Filed Jan. 23, 1964, Ser. No. 341,479 s claims. (Cl. 181-33) This application is a continuation-in-part of my copending application Serial No. 106,409, filed April 28, 1961 and now abandoned.

This invention relates to acoustic tile adapted to be secured to a ceiling or the like.

It has been conventional heretofore to make acoustic ceiling tile from a perforated fibrous material. Also, it is known in the acoustic 4tile art to provide a perforated acoustic tile with a rubber-like backing. For example, see U.S. Patents 2,573,482 and 2,959,242.

The rubber-like backing in the above-identified patents consists of an inexpensive rubber composition having high energy absorption ruch as vulcanized soft rubber or sponge rub-ber. I have discovered that the amount of sound-deadening can be increased by utilizing a polymeric backing which is materially different from the rubber-like backing disclosed in the above-identified patents.

The acoustic tile of the present invention comprises a perforated brous material secured to a polymeric backing which is both a sound reflecting material and which has a high specic gravity, namely a specic gravity greater than 1.35. Contrary to the disclosure in the aboveidentified patents, the polymeric backing of my acoustic tile reilects sound back into the iibrous material rather than absorbs the sound which passes through the fibrous material.

It is an object of the present invention to provide a novel acoustic -tile which does not transmit sound to a wall surface.

This and other objects are provided by the acoustic tile wherein a perforated fibrous material is provided with a high specic gravity sound reflective polymeric backing, or where the acoustic tile comprises a sandwich of a high specific gravity sound-reflective polymeric material disposed between perforated fibrous layers.

For lthe purpose of illust-rating the invention there is shown in the drawings forms which -are presently preferred; it being understood, however, that this invention is not limited -to the precise arrangements and instrumentalities shown.

FIGURE 1 is a transverse sectional view of a ceiling having the novel acoustic tile of the present invention secured thereto.

FIGURE 2 is a transverse sectional view of a ceiling disclosing another embodiment of Ithe present invention secured thereto.

Referring to the drawing in detail, wherein like numerals indicate like elements, there is shown in FIGURE 1 an acoustic tile designated generally as 10.

The acoustic tile of the present invention is adhesively secured to a ceiling 12 by a layer of adhesive 13. It will be obvious to those skilled in the art that other securing means such as nails may be substituted for the layer of adhesive 13.

The tile 10 comprises a layer 14 of high specific gravity vulcanized rubber. It has been discovered that high specific gravity vulcanized rubbers will reflect rather than absorb sound. High specific gravity vulcanized rubbers are commercially available products. An example of a rubber which has properties suitable for use in the present invention is X-l-B hard rubber having a specilic gravity of 1.40-1.44 manufactured by the American Hard Rubber Co. A layer of brous material 16 is adhesively 3,229,785 Patented Jan. 18, 1966 secured to the layer 14 by adhesive 1;8. The layer 16 is provided With a plurality of holes 20 therethrough.

Sound waves are absorbed by the layer of fibrous material 16. As is well known in the art, the holes 20 in the layer 16 assist in absorbing such sound waves. A small portion of the sound waves are not absorbed by the layer 16. Such portion of the sound Waves are reflected by the layer 14 .back into the layer 16. As the reflected waves pass through the layer 16 they are absorbed by the layer 16. Accordingly, sound waves do not reach the ceiling 12.

FIGURE 2 discloses an alternative embodiment of the present invention designated generally as 10. The tile 10 includes a layer 14' of high specific gravity vulcanized rubber material adhesively secured to a layer of fibrous material 16 by adhesive 22. The layer 14' is sandwiched between layers 16 and 26. The layer 26 is of fibrous material and is adhesively secured to the layer 14 by adhesive 24.

The acoustic tile 10' is adapted to be adhesively secured to a .surface of the ceiling 12 by adhesive 28. The acoustic tile 10 is a bonded laminated structure adapted to be utilized in rooms wherein the sound intensity is very great. When the sound intensity is very great, there is a possibility of a small portion of the sound passing through the layer 14. Such sound waves are absorbed by the layer 26 thereby preventing the `passage of the same into the ceiling 12'.

It will be noted that the layers 16 and 26 of fibrous material are provided with holes similar to holes 20 in the layer 16. Also, it will .be noted that the holes in the layers 16 and 26 are offset from one another. The offset nature of the holes in the layers 16 and 26 assures complete sound absorption.

The material for the layers 16, 16 and 26 is well known to those skilled in the art. Accordingly, a detailed explanation of such material is not required. While the layers 14- and 14 are disclosed as being a high specific gravity vulcanized rubber, other high speciiic gravity sound-reflective polymeric materials may be substituted therefor.

For example, the following high specic gravity soundreilective materials are suitable for use in the present invention:

(a) High specific gravity chloroprene rubber having a specic gravity of about 1.8 sold as Neoprene by E. I. DuPont de Nemours & Co., Wilmington, Delaware.

(b) High specific gravity asphaltic material, a wide variety of high specific gravity sound-reflective asphaltic materials having specic gravities appreciably greater than 1.35 have been prepared by blending clays with asphalt, and are commercially available. Some natural asphalts, such as Trinidad Asphalt, contain clay and have a high specific gravity.

(c) High speciiic gravity polyvinyl chloride elastomer, such as vinyl durometer) having a specific gravity of 1.35 described at page 15 of Union Carbide Plastics Companys Bakelite Review of April 1962.

As with the high specific gravity sound-reilecting asphaltic material described above, the term sound-reflective high specific gravity polymeric material as used in the appended claims includes a polymeric mixture having an overall specic gravity of greater than 1.35 of a polymer having a specic gravity of below 1.35 and dense particles of metal, clays or other illers uniformly dispersed through the polymer which raise lthe overall specific gravity of the polymeric material to above 1.35. A wide variety of sound reflecting polymers having uniform dispersions of high specific gravity metals, such as lead, or aggregates such as in the material called Amiesite,

disposed therewithin, have been prepared, and can be used in the acoustic tiles of the present invention.

The present invention may be embodied in other specic forms without departing from the spirit or essential attributes thereof and, accordingly, referenceV should be mad'e to the appended claims, rather than to the foregoing specification as indicating the scope of the invention.

I claim:

1. An acoustic tile comprising a rst layer of fibrous sound absorbing material, said first layer having holes extending therethrough, said first layer being juxtaposed to and adhesively secured to Ia second layer, said second layer being a sound-reflective polymeric material having a specific gravity of 1.35 or greater.

2. An acoustic tile in accordance with claim 1 Wherein said high density sound-reflective polymeric material is a vulcanized rubber.

3. An acoustic tile in accordance with claim 1 in which said high density sound-reilective polymeric material is an asphalt-clay mixture.

4. An acoustic tile comprising a layer of sound-reflective polymeric material sandwiched between layers of perforated sound absorbing material, the speci-iic gravity of said layer of sound-reflective polymeric material being 1.35 or greater, said layers being bonded together to form a laminated structure.

5. An acoustic tile in accordance with claim 4 wherein said layer of sound-reflective polymeric material is vulcanized rubber.

6. An acoustic tile in accordance with claim 4 wherein said layer of sound-reective polymeric material is an asphalt-clay mixture.

References Cited by the Examiner UNITED STATES PATENTS 1,945,308 1/1934 Fischer 181-33 2,159,488 5/1939 Parkinson 181-33 2,184,482 12/1939' Austin et al. 181-33 2,240,014 4/1941 Peik 181-33 2,240,015 4/1941 Peik 181-33 2,742,374 4/1956l Groskopf 181-33 2,959,242 11/ 1960 Muller et al. 181-33 2,999,041 9/ 1961 Lappala 181-33 3,087,574 4/ 1963 Watters 181-33 3,126,978 3/1964 Bergstrom 181-33 3,130,700 4/ 1964 Peterson 181-33 p FOREIGN PATENTS 532,453 10/1956 Canada. 604,197 8/ 1960 Canada. 1,220,354 1/ 1960 France.

OTHER REFERENCES Automotive Industries,Periodical, issue of September 1, 1959, page 31.

LEO SMILOW, Primary Examiner.

R. S. WARD, Assistant Examiner. 

1. AN ACOUSTIC TILE COMPRISING A FIRST LAYER OF FIBROUS SOUND ABSORBING MATERIAL, SAID FIRST LAYER HAVING HOLES EXTENDING THERETHROUGH, SAID FIRST LAYER BEING JUXTAPOSED TO AND ADHESIVELY SECURED TO A SECOND LAYER, SAID SECOND LAYER BEING A SOUND-REFLECTIVE POLYMERIC MATERIAL HAVING A SPECIFIC GRAVITY OF 1.35 OR GREATER. 